Illegitimate son of Henry I Beauclerc, born in Caen (the identity of his mother is controversial), Robert Fitzroi (son of the king) is represented as both an academic and erudite prince, in particular supporting William of Malmesbury and Geoffrey of Monmouth, but also as a great warrior very active in Anglo-Norman affairs. Named Count of Gloucester in 1122, he possesses significant estates in England and Normandy, in particular in the diocese of Bayeux (Creully, Thaon, etc.). Married to the daughter of Robert Fils Hamon, Lord of Creully, he succeeds his father-in-law after the battle of Tinchebray (1106) as lord of the manor charged with the command of the Château de Caen. On the death of Henry I in 1135, he sides with his half-sister Mathilda and supports the invasion of Normandy by Geoffrey of Anjou. In England, he leads the fight from his fortress at Bristol. In 1141, he captures Étienne de Blois at Lincoln. He dies in 1147 and is buried in the Benedictine priory of Saint-James in Lincoln which he founded.